Key points about patellar tendon tear
- A patellar tendon tear affects the tendon that connects the kneecap to the shinbone.
- It can be caused by a sudden impact, jump or overuse injury.
- Common symptoms include pain, swelling and an inability to straighten your leg.
- Diagnosis involves a physical exam and imaging like X-ray or MRI.
- Surgery is often needed for complete tears, followed by rehabilitation.
Common related conditions
Patellar tendon tear causes
Physical activity is usually the main cause of a tear, usually while playing sports or exercising. It can also be caused by:
- Sudden forceful contraction of the thigh muscles (like jumping or landing)
- Direct trauma to the front of the knee
- Chronic tendon inflammation or overuse (commonly known as jumper’s knee)
- Weakness due to prolonged inactivity or certain medical conditions
Patellar tendon tear risk factors
Athletes are often the main candidates for tearing their patellar tendon, but other factors can contribute, including:
- Athletes in jumping sports like basketball, volleyball or track and field
- Previous tendon problems or knee surgeries
- Systemic conditions like diabetes or kidney disease
- Use of corticosteroids or certain antibiotics
- Aging, which reduces tendon strength and elasticity
Patellar tendon tear symptoms
Chances are you’ll probably know something in your knee isn’t right immediately after a tear. You may also experience:
- A sharp pain at the front of the knee
- Hearing an audible pop or snap at the time of injury
- Having difficulty or a complete inability to straighten your leg
- Swelling, bruising and possible deformity just below the kneecap
- Weakness and instability when trying to walk
Patellar tendon tear diagnosis
To determine if you’ve torn your patellar tendon and the degree in which you’ve torn it, a doctor may perform a:
- Physical exam assessing knee function and tendon integrity
- X-ray to evaluate kneecap positioning
- MRI to confirm the extent of the tendon damage and rule out other injuries
Patellar tendon tear treatment
Treatment for a torn tendon will vary depending on how severe the tear is, but can include:
- Rest, ice and immobilization for minor partial tears
- Surgical repair for full-thickness or complete tears
- Post-surgical rehabilitation to restore movement and strength
- Use of knee braces or crutches during initial recovery
- Gradual return to activities with guided physical therapy
When to Seek Care
- Sudden pain and inability to straighten or bear weight on the leg
- A visible gap or abnormal positioning of the kneecap
- Swelling and bruising after a jump or fall
- Knee instability or a sensation of giving out
- Persistent knee pain and weakness following tendonitis or overuse